A problem in extraction of geothermal energy and other isolated energy sources, such as nuclear power plants, has been that a heat-conductive fluid must first be pumped to the heat source, where the fluid is heated, then pumped back to a heat exchanger to be extracted for useful purposes or ejected. The cooled fluid output of the heat exchanger may be reused in some applications, or may be waste in other applications, but requires pumping in either case. The heat losses during pumping from the isolated heat source to the heat exchanger can be substantial, so only the hotter geothermal or other isolated sources are practical to use. With geothermal energy, this often requires adding the cost of drilling both a production well and an injection well to discharge expended geothermal fluids.
Therefore, a need exists for a heat conduction medium that does not require pumping.